Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1034296AbcJ0XEo (ORCPT ); Thu, 27 Oct 2016 19:04:44 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:45263 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933403AbcJ0XEl (ORCPT ); Thu, 27 Oct 2016 19:04:41 -0400 Date: Fri, 28 Oct 2016 00:37:45 +0200 (CEST) From: Thomas Gleixner To: Ye Xiaolong cc: Alex Thorlton , LKML , Mike Travis , Russ Anderson , Dimitri Sivanich , Ingo Molnar , "H. Peter Anvin" , Matt Fleming , Masahiro Yamada , x86@kernel.org, lkp@01.org, Peter Zijlstra Subject: Re: [lkp] [x86/platform/UV] 71854cb812: will-it-scale.per_thread_ops -2.3% regression In-Reply-To: <20161027015508.GG21890@yexl-desktop> Message-ID: References: <20161025064647.GB3341@yexl-desktop> <20161027015508.GG21890@yexl-desktop> User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 Content-Type: multipart/mixed; BOUNDARY="8323329-892428444-1477607867=:4913" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1519 Lines: 37 This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --8323329-892428444-1477607867=:4913 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8BIT On Thu, 27 Oct 2016, Ye Xiaolong wrote: > Yes, this is weird, the per_thread_ops change is small and should be run > to run variation, the actual significant change is will-it-scale.time.user_time > -27% decrease, but the patch seems not relevant, we can't interpret it. :( > > We've tried to queue the jobs (4 times) for > 71854cb812ec23bfe5f63d52217e6b9e6cb901f5 and v4.9-rc1 with new kconfig > (added CONFIG_DEBUG_INFO_REDUCED), and result shows user_time change is > quite stable. > v4.9-rc1 71854cb812ec23bfe5f63d5221 > ---------------- -------------------------- > %stddev %change %stddev > \ | \ > 1670068 ? 0% -3.8% 1606650 ? 1% will-it-scale.per_thread_ops > 9749 ? 2% +1328.0% 139222 ?105% will-it-scale.time.involuntary_context_switches ^^^^^^ This is massive I have no explanation for this either, but you really should try to figure out what's going on here. The only difference between plain rc1 and rc + this patch is the resulting text size and therefor some other unrelated stuff moving to different places in memory which has some yet to figure out side effects. Thanks, tglx --8323329-892428444-1477607867=:4913--